sphalt is the most recycled materials around the world and the amount of RAP materials can be significantly increased with the application of good RAP management applications. In Iraq, the real inclusion of RAP materials in asphalt mixtures has not been applied yet in the field. It is therefore that there is a need to characterize the effect of inclusion RAP materials in asphalt mixtures with particular reference to permeant deformation/rutting resistance. The aim of this study is to evaluate the best layer of pavement structure; base, binder, and surface layers for inclusion (RAP) materials. In addition, highlight the best percentage that can be added from RAP to achieve positive results and better than that associated reference mixture in terms of rutting resistance. RAP materials collected from different sources Karbala and Fallujah, were adopted in this study at percentages of 20%, 30%, and 40% by weight of the asphalt mixture. Two scenarios of incorporating RAP materials have been adopted. The first is considered that RAP as a black rock in which the effect of aged binder surrounding the aggregate of RAP is neglected while, the letter is not considered RAP as black rock and the influence of aged binder in RAP materials has been taken into consideration. Dora bitumen has adopted in the current study which is used in common in Iraq. It has been highlighted the best layer in which RAP can be incorporated is the base layer, with a percentage up to 40% that RAP without considering RAP black rocks regardless the sources of RAP.
Bitumen is a standard material for road infrastructure that is black in color, sticky, and thermoplastic in nature. It is well-known for its many applications. Due to rising traffic, global warming, and the constant introduction of new pavement varieties, forecasting road life has become increasingly complex in recent years. At the same time, a significant quantity of vehicle tires and waste engine oil (WEO) from different cars are dumped into the environment as hazardous waste. Additionally, it has been challenging to manage heavy metals and the substantial costs associated with their sustainable treatment. Therefore, this study looks at how Waste Engine Oil (WEO) and Crumb Rubber Modifier (CRM) affect the characteristics of PEN60-70 asphalt binder. The asphalt binder has been subjected to several tests at different temperatures due to the use of various concentrations of CRM and WEO. To reduce the usage of virgin bitumen (VB) and make bitumen a sustainable material, this study investigates modified bitumen using a waste crumb rubber modifier (CRM) combined with WEO. These WEO concentrations (5% and 10%) and CRM concentrations (0%, 4%, 8%, and 12%) were used in the characterization of modified bitumen, and then the characteristics of virgin and modified bitumen were compared. According to the study, adding WEO to CRM-modified binders reduces softening points by increasing penetration, as well as viscosity and workability, while CRM enhances rutting resistance. Nevertheless, the incorporation of WEO has a detrimental effect on the binder's ability to resist rutting. The study's findings also indicate that the use of WEO and CRM can enhance the resilience of asphalt mixtures to low-temperature cracking. According to the study's findings, adding WEO to co-modify CRM binders significantly reduced their softening point and viscosity values, making them easier to work with. Ultimately, the modified asphalt was found to exhibit positive rheological and physical modifications in the bitumen.
A sample of 50 randomly selected rural and urban roads of Ramadi district were observed for asphalt pavement Distresses. Three main types of Distresses were considered; rutting, cracks and pavement separation. In addition, different other Distresses types that were observed were grouped in one category named "Other". For each road, information about the age of the pavement was recorded. Kaplan-Meier method was carried out in order to understand the Remain time before pavement deterioration as well as to compare pavement service life with respect to the type of Distress. Results of this research revealed significant differences between pavement service life corresponding to the type of Distress. Pavement service life appeared to last less than 20 months when all the mentioned types of Distresses are occurred on the road